SCraMP 3.7 is in the app store (free, as always).  Based on user requests, v3.7 has a compass and heading information.  Also included, for my data acquisition users, is a choice of coordinate systems.  The API implementation by Apple is an earth fixed coordinate system (some of you may have noticed this if you were playing with the app at large angles), so now you have a choice of a body-fixed system (i.e., what roll/pitch/yaw usually mean to boat or airplane people) or the earth-fixed system.  Last, but certainly not least, the app now stores your preferences.  For example–enter your boat’s beam once and be done with it; no more having to enter that every time you re-launch the app and want to use the GM estimate!  As always, I’m eager to hear your feedback: scramp@vesseldynamics.com